Joining 2D tracking markers with an offset
To track areas that are blocked by obstacles or temporary going off-screen. Move the tracking marker before the area is hidden by pressing GG and dragging the marker to another tracking point, or offsetting the marker in Track properties panel in Marker section by changing X and Y offset position. You can then continue tracking the scene under the offset tracking area until the original tracking area is visible again, then move the marker back using the same procedure.